1. Field of the Invention
The present invention relates to a photographing control apparatus and a photographing control method, and particularly relates to a control apparatus and a control method for controlling a shooting direction of a camera.
2. Description of the Related Art
Conventionally, a viewer client application connected to a camera adaptable to a network can control the camera and receive a video through the network. In addition, there is a viewer client application which can control the camera by designating an arbitrary position in an image display area of an application screen, with a pointer of a mouse, or the like.
As described in US 2001/019355 A1, for instance, a viewer application is proposed which controls a camera so that when a user has designated an arbitrary position in a panorama image, the position comes to the center.
The imaging apparatus described in US 2001/019355 A1 controls the camera so that the designated position in a panorama image display area comes to the center of the image, but actually is restricted by its mechanism, and accordingly occasionally cannot necessarily control the camera so that the designated position comes to the center of the image.
FIG. 2 is a conceptual view illustrating a relationship between a quantity of moving of a lens barrel unit and an optical zoom.
The lens barrel unit 20 is pan driven by a motor. The quantity of moving per one pulse to be given to the motor is determined as characteristics of the motor, and the quantity of moving is relatively small with respect to an angle of view in the approximate boundary 22 of an optical wide, but is relatively large with respect to the angle of view in the approximate boundary 21 of an optical tele. This tendency becomes more remarkable as a zooming ratio becomes higher.
An influence of this quantity of moving on a screen to be viewed by a user on the viewer client application is considered as follows. For instance, suppose that a user designates a position of a pointer 301 in a display screen 300 in FIG. 3, in the case of the approximate boundary of tele. In this case, the user expects that the camera is controlled so that the position designated by the pointer 301 comes to the center as in a display screen 310, but actually such a situation can occur that the marked position results in largely exceeding the center as in a display screen 320.
Accordingly, there have been such problems that the camera seems to have largely exceeded the center or have not been entirely controlled to the user, depending on the designated position of the image display area, and accordingly that the user feels anomalous.